The present invention relates in general to working vehicles, and more particularly, to cooling systems in working vehicles.
U.S. Pat. No. 3,636,684 discloses a harvesting machine having a fan 72 which pulls air into an engine enclosure 50 through screens, wherein the air passes through a radiator core 56 prior to exiting the enclosure 50, see column 5, lines 54-59.
U.S. Pat. No. 3,664,129 discloses a lift truck including “a hydraulic motor-driven cooling fan, the speed of which is varied with engine temperature,” see column 1, lines 42-44 and column 3, lines 15-20. “The fan blades draw engine-heated air rearwardly through radiator core 18 and push such air through air duct 28 and out through the rear end of the truck,” see column 3, lines 20-22.
U.S. Pat. No. 6,959,671 discloses a cooling system for a work vehicle wherein a “rotational speed of the cooling fan 13 actuated by the hydraulic pump 18 is continuously controlled according to the temperature of the coolant, the temperature of the hydraulic oil and the rotational speed of the engine,” see column 5, lines 3-7. The '671 patent also teaches that the direction of the fan may be reversed such that “dust or the like caught in the radiator 12 is blown off by a reverse current of air,” see column 5, lines 24-30.